1. Field of the Invention
At least one embodiment of the present invention relates generally to detection of fluid levels, and more specifically, to optical determination of information related to a liquid depth in a condensation pan of heating, ventilating, and air conditioning devices.
2. Discussion of the Related Art
Heating, ventilating, and air conditioning (HVAC) devices are used for a variety of climate control applications to regulate temperature or humidity levels of an environment such as a room. When performing a cooling operation, condensation forms on cooling or evaporation coils of the air conditioning unit as latent heat is extracted from the environment. This condensation gathers as a pool of water beneath the air conditioning evaporation coils. This water can be collected in a container but eventually must be removed to prevent overflow or leakage. Unintended water flow or stagnation can damage the HVAC device or its surroundings.
Existing schemes for controlling water flow and placement due to condensation during HVAC operation utilize mechanical devices such as float switches; capacitive switches; sensors detecting conduction or pressure changes; weighing a container in which water has collected; or tracking volumetric loads delivered to the container. However, these types of HVAC water control and displacement systems are not without their drawbacks, as these control systems have mechanical size and space constraints and are prone to corrosion, inaccurate, difficult to monitor, and susceptible to long term degradation.